Alfa has not released a driver package for Alfa AWUS036NHA (Atheros AR9271 chipset) beyond Windows 7.
However it has come to our attention that AWUS036NHA can be stable on Windows 8, 10, and 11 using this third party driver. This driver was made for a different brand product which uses the same AR9271 chipset. Note that after installing, the device will appear in Device Manager as "TP-LINK Wireless USB Adapter" instead of Atheros or Alfa. This is because TP-Link is associated with Microsoft as the Device Developer ID of this driver package.
We have tested the driver extensively and it appears to work with the Alfa AWUS036NHA well. However it should be considered a beta driver until further notice.
Military and First Responder 
I had the hardest time getting my Alfa AWUS036NHA to work on Windows 10. It said everything was working fine, but it wasn’t. Almost gave up until I ran across this solution and it worked perfectly. Easy to set up as I am not a computer geek. Download and run it and it basically does the rest. Didn’t have to uninstall any other driver or anything like that. I did disable the stock wireless adapter in my computer though. Did this to two different computers and it worked perfectly for both.
September 2019 – I too can confirm this works on Win10 :)
trying in now. will update
I downloaded drivers from their official website for windows 10 and it is not working, Showing me code 10 error for the device in device manager,.
on their official website, it is saying that drivers are compatible for windows 10
Works fine. I’ve tried loads of “solutions” and this is the ONLY one that actually works. Thanks!